Chlorobutadiene



enema Jan. 14,1936 2,027,550 r UNITED STATES PATENT OFFICE emaommanmnn Granville a. Perkins, South Charleston, w. Va.,

assignor to Carbide and Carbon Chemicals Corporatiomacorporation or New York No Drawing. Application August 15, 1931,

Serial No. 557,42!

9 Claims. (Cl. 260- -162) The invention relates to a new chloro derivasodium chloride tor the calcium chloride, and the tive of 1,3 butadiene, and-includes a process for proportion of hydrochloric acid may be varied. making the new compound. The latterisacolor- It is essential to have the catalytic solution in less liquid having a specific gravity of 0.945 at 21 the second step strongly acid. The cuprous chlo- C. and a boiling point of 56 to 59 C. It appears ride may be added as such, or it may be produced 5 to have the structural formula in the solution in any suitable manner; for example, by adding metallic copper and chlorine, H2C CH CC1 CH2 cuprous oxide, or any cuprous compound which and is probably 2-chlorobutadiene-1,3. The new will yield solutions equivalent to those produced a 10 compound undergoes spontaneous polymerization by hydrochloric acid and cuprous chloride- The 10 forming a homogeneo ,amorphous, elastic solid catalytic solution may be used repeatedly, hywhich resembles caoutchouc in its physical drogen chloride being passed in to replace that properties, but which has the empirical composiwhich is consumed in the reaction. tion of chlorobutadiene (C4H5Cl) I Solvents similar to toluene, particularly hydro- The compound can be prepared by the intercarbons such as xylene, kerosene or mineral oils, 15 action or vinyl acetylene (CH2=CH-C=CH) may be used, and the solvent may be repeatedly with hydrogen chloride in the presence of a catautillzed in the process. The solvent used should lyst comprising a cuprous compound. The procbe inert with respect to the reagents oi the process is illustrated by the following example: ess and immiscible with water. The solvent 1 Vinyl acetylene was prepared by dissolving 300 may be dispensed with entirely and other means 20 grams oi! calcium chloride, 300 grams of cuprous of removing the reaction product may be subchloride and '10 cc. of concentrated hydrochloric stituted. For example, the product may be reacid in 600 cc. 0! water. Acetylene was bubbled moved by passing an excess 0! gaseous vinyl through this solution until it became nearly coloracetylene through the solution and isolating the less. Ammonium hydroxide was then slowly chlorobutadiene by iractionating means from the 2| added to the solution until 'a precipitate formed, issuing gaseous mixture. and a little hydrochloric acid was added to redis- I claim: solve the precipitate. The solution was then 1. A process for making 2-chlorobutadieneready for use. Acetylene was bubbled through 1,3 which comprises reacting vinyl acetylene with the solution at the rate of about 10 liters per aqueoushydrogen chloride in the presence of a 80 hour, and 2.5 grams per. hour of vinyl acetylene, catalyst consisting essentially of cuprous chloride, boiling at about 5 C., were recovered from the and in the presence of a water-immiscible inert issuing gases by means of condensation and iracsolvent in which the product is dissolved. tional distillation. 2. A process for making 2-chlorobutadiene-l,3 A strongly acid catalytic solution was then prewhich comprises reacting a solution of vinyl as pared by dissolving 100 grams or calcium chloride acetylene in a water-immiscible inert solvent with and 100 grams of cuprous chloride in a mixture an aqueous solution of hydrogen chloride in the composed of 200 cc. of concentrated hydrochloric presence f a Wa Soluble cuprous mI lm acid and cc. of water. This'solution was agiand thereafter isolating z-chloroblitadiene-ha 40 tated with powdered copper to reduce traces of from said solution. 40 cupric salts which were'present as evidenced by 3. A process for making 2-chlorobutadiene-l,3 the dark color of the solution. Forty-two grams .whlch comprises reacting vinyl acetylene with an or vinyl acetylene dissolved in 200 cc. oi'toluene aqueous solution of hydrogen chloride and cuwas then added to this solution and the two layers prous chloride which contains a soluble chloride .4 were intimately mixed by shaking. Heat was of an alkaline earth metal. d5 evolved during this operation indicating that a 4. A process for making 2-chlorobutadiene-L3 rapid reaction took place. When the toluene which comprises reacting vinyl acetylene with layer no longer produced a yellow precipitate hydrogen chloride in the presence of a catalyst with ammoniacai cuprous chloride, it was sepaconsisting of a water soluble cuprous compound 5 rated and distilled in the presence of water.- The and removing theproduct from the zone of reac- 60 fraction distilling at 52 to 55 C. under these contion as it is formed by the aid of a water-immisditions was found to be a chlorobutadiene, probcible inert solvent in which said product is disably 2-chlorobutadiene-1,3. solved. The process may be varied by substituting other 5. A process for making 2-chlorobutadiene-1,3 55 chlorides, such as ammonium, potassium, or which comprises reacting vinyl acetylene with an ll aqueous solution of hydrogen chloride and cuprous chloride which lontains a soluble chloride 01 an alkaline earth metal, and removing the product oi reaction as it is formed.

6. A process for making 2-chlorobutadiene-l,3 which comprises passing an excess of gaseous vinyl acetylene through an aqueous solution of hydrogen chloride and cuprous chloride which contains a soluble chloride or analkaline earth metal, and isolating the product of reaction from the excess vinyl acetylene.

7. A process for making 2-chlorobutadiene--1,3 which comprises agitating a solution of vinyl acetylene in a water-immiscible inert solvent with an aqueous solution of hydrogen chloride and cuprous chloride which contains a soluble chloride or the group consisting of ammonium, alkali metals and alkaline earth metals, and thereafter isolating 2-chlorohutadiene-L3 from said solvent.

8. A process for making 2-chlorobutadiene-1,3

which comprises agitating a solution of 1 part by weight of vinyl acetylene in about 5 parts by weight oi a water-immiscible inert solvent with an aqueous solution composed of approximately 2.5 parts by weight each of hydrogen chloride, calcium chloride and cuprous chloride and about 3.5 parts by weight of water, and thereafter isolating Z-chIorobutadIene-IB from said solvent by fractional distillation.

9. A process for making 2-chlorobutadiene-1,3 which comprises agitating a solution of 1 part by weight of vinyl acetylene in about 5 parts by weight 01' toluene with an aqueous solution composed of approximately 2.5 parts by weight each of hydrogen chloride, calcium chloride and cuprous chloride and about 35 parts by weight of water. and thereafter isolating 2-chlorobutadime-1,3 from said solvent by fractional distiila tion.

GRANVILLE A.- PERKINS. 

